1. Field of Invention
This invention concerns novel water-resistant, and versatile phenolic adhesive products and glue derived from algal materials. In particular, the phenolic compounds of this invention act as adhesives by binding non-specifically to both hydrophobic and hydrophilic surfaces under water and are thus useful for medical, biological, biomedical, marine, industrial and other applications. The invention further relates to algal-derived glues and adhesive products containing activated phenolic component. The activation may be achieved with algal peroxidase catalysts. The activated phenolic may be cross-linked with algal carbohydrates and other fibers.
2. Background Art and Related Disclosures
The ability of various aquatic and marine organisms such as mussels, barnacles, oysters or algae to adhere to various surfaces under water is well known.
For many years, attempts were made to identify the mechanism by which these organisms achieve such strong adhesive bonding, to determine whether the same or similar mechanism could be used to produce a water-resistant adhesive. Typically, these attempts led to formation of adhesives of various strengths. Many of the adhesives would bind either to hydrophobic or hydrophilic surfaces, but not both.
For example, J. Microbiol., 12:139 (1990) describes marine adhesive proteins consisting of fibers such as, collagen, fibroin, or chitin, fillers such as sand, shells, air or water and catalyst molecules that are dispersed in cross-linked resin. The marine adhesive resins are typically proteins containing high levels of DOPA.
Phenolic resin adhesives that are the product of an oxidative reaction occurring in the presence of peroxidase or oxidase catalyst are generally disclosed in U.S. Pat. Nos. 4,900,671 and 5,112,752. Suitable oxidative catalysts used in production of these resins are horseradish peroxidase and peroxidase from soybeans, legumes and higher plants. The resin adhesives described are not cross-linked for enhanced adhesive strength nor do they possess both hydrophilic and hydrophobic properties for broad adhesive application.
Phenolic compounds activated with peroxidase enzymes are also disclosed in U.S. Pat. No. 5,030,538 for use as developer layers in transparencies for overhead projection. Phenolic compounds having hot melt adhesive characteristics are disclosed as particular developer layer embodiments.
Abstract P20B, entitled "Non-gelling Wall Interactions of Alginate in Fucus Zygotes Correlate With Adhesion" presented in June 1990 at American Society for Cell Biology Summer Conference at Airlie, Va. discloses the formation of alginate-Fucan and alginate-phenolic interactions in brown alga Fucus zygotes.
None of the above disclosures provide adhesive glue that (i) forms quickly and easily in aqueous conditions without the use of expensive reagents and complicated procedures and (ii) possesses the ability to bind to both hydrophobic and hydrophilic surfaces, and (iii) is water-resistant and environmentally safe.
It would, therefore, be advantageous to provide adhesives which are able to bind with great strength to both hydrophobic and hydrophilic surfaces under water, are water-resistant and otherwise generally inexpensive and versatile.
It is, therefore, a primary object of the present invention to provide a stable aqueous adhesive comprising phenolic containing products derived from naturally occurring brown algae (Phaeophytes), red algae (Rhodophytes), and related algae that are safe, water-resistant, capable of binding, with great strength, to both hydrophobic and hydrophilic surfaces of materials, resistant to destruction by various agents that destroy previously known protein containing adhesives, and readily formed in aqueous conditions from dry product without resort to complex reactions and procedures.
It is a further object of the present invention to prepare adhesive phenolic products that are substantially cross-linked for greater adhesive strength and additionally have both hydrophilic and hydrophobic properties to broaden their suitability for adhesive applications.
It is yet a further object of the invention to prepare an adhesive that consists essentially of naturally occurring algal phenolic compounds.
It is yet a further object of the invention to prepare adhesive phenolic products that comprise naturally occurring algal phenolic compounds that are activated with an oxidizing agent in the presence of a naturally occurring algal peroxidase enzyme and/or are covalently cross-linked with algal carbohydrate or other fibers.